Time taken by light to travel in two different materials A and B of refractive indices μA and μB of same thickness is t1 and t2 respectively. If t2 – t1 = 5 × 10–10 s and the ratio of μA to μB is 1 : 2. Then, the thickness of material, in meter is: (Given vA and vB are velocities of light in A and B materials, respectively.)
5 × 10-10 vA m
5 × 10-10 m
1.5 × 10-10 m
5 × 10-10 vB m
The Correct Option is A
Solution and Explanation
\(\frac{\mu_A}{\mu_B}\)=\(\frac{\frac{c}{V_A}}{\frac{c}{V_B}}\)=\(\frac{V_B}{V_A}\)=\(\frac{1}{2}\)
Let the thickness be d
\(\frac{d}{v_B}\)−\(\frac{d}{v_A}\)=5×10−10
d=5×10−10×\(\frac{v_Av_B}{v_A-v_B}\)
As vA=2vB
⇒d=5×10−10×2vB
Or
d=5×10−10×vA
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Concepts Used:
Light-Dependent Reaction
One of the major surfaces of Light Reaction is giving rise to organic energy molecules, such as ATP and NADPH, which are especially necessary for the subsequent occurrence of the dark reaction that works without the presence of sunlight.
- During the process of light reaction, the elemental step involves chlorophyll absorbing the energy released from the sunlight and transforming it into chemical energy in the appearance of electron charge carrier molecules, like ATP and NADPH, with photosynthesis happening or occurring subsequently.
- This procedure in general takes place in large complexes of protein, called Photosystems, which are further categorized into PSI and PSII.
- The elevated pigments of chlorophyll then give their electrons up. In order to recompense for the loss of electrons, water is usually cleaved to discharge four H+ ions, four electrons, and O2.
- The lost electrons of the PSII further enter ETC, concise or abbreviated from Electron Transfer Chain. Upon entering ETC, the electrons unite with NADP+, bringing it down further to NADPH.
- There is a subsequent movement of electrons that is used for the transportation of hydrogen ions over the thylakoid membrane.
- The H+ ions, subsequent to building up within the lumen, help build a layer of a positive gradient. These H+ ions, in the presence of ATP synthase, combine with the ADP to further form ATP.
- Oxygen, afterward, which holds on to as a waste product gets released into the atmosphere.